Field of the Disclosure
This disclosure relates generally to a filtered needle for safely administering pharmaceuticals or other liquid payloads needing filtration before administration to a patient. The filtered needle may be used with human patients, veterinary uses for animals, and other uses that benefit from the filtering of a liquid payload before delivery. In this disclosure and the claims that follow, the term needle should be understood as a hypodermic needle or analogous needle with an open distal end and an interior lumen to allow for movement of a liquid.
Liquid pharmaceuticals are typically stored in sealed glass ampoules (often spelled ampule) or other known storage devices. In the case of glass ampoules, order to gain access to the pharmaceuticals, the ampoule is opened by snapping the glass neck. In so doing, debris in the form of glass shards may be produced. The shards must be removed from the pharmaceuticals prior to administration. The debris is typically removed by drawing up the pharmaceutical through a filtered cannula or straw secured to the end of the syringe.
While the most common use of a syringe to deliver liquids is to deliver a liquid pharmaceutical, other liquid payloads can be drawn in from a reservoir through a filter to remove debris before delivering the filtered liquid payload through a needle connected to the syringe.
Examples of uses beyond pharmaceuticals include the injection of some nutraceuticals into a patient. Some public health organizations provide needle exchanges to people addicted to illegal drugs as a way to limit spread of disease and a filtered needle may be of benefit in this application. Some blood products such as PCC (Prothrombin Complex C) use a filtered needle. The list of uses should not be deemed a limitation to the scope of the claims as those of skill in the art will be able to adapt the teachings of the present disclosure for use with a particular liquid payload and need for filtration.
Methods for removing debris include a two stage process and a one stage process. In the two stage process, a needle or straw has a filter element secured in the needle and connector portion. As the liquid payload is drawn up into the syringe, the filter traps the debris removing it from the liquid payload to be administered. The filtered straw or needle is then removed from the syringe and discarded. In order to avoid inadvertent administration of contaminated liquid payload to the patient, care must be taken to remove and discard the filtered needle. In addition to the danger of mistakenly administering a contaminated liquid payload to a patient, the two stage process may involve the use of specially adapted and costly disposable devices.
U.S. Pat. No. 8,002,751 for Filter Needle discloses a one-step process. This one step process employs a specially fabricated frangible needle or straw which has a filter secured near the inlet. The needle or straw has a score line between the filter and the syringe connection. The pharmaceutical is first drawn up from the ampoule through the filter trapping the debris. The tip of the needle or straw is then snapped off along the score line and discarded, taking with it the filter and trapped debris. The one stage process requires a specially fabricated needle or straw which may be snapped off leaving a sharp end for administering the pharmaceuticals. It is difficult to manufacture a needle having the required properties. In addition, questions have been raised as to whether a frangible needle or straw may be produced which does not itself produce debris, such as metal or plastic shards.
Accordingly, an inexpensive and reliable system for filtering liquid payloads before delivery is desired.